JT Poston seized a four-stroke lead over fellow American Ryan Gerard after Sunday morning's completion of the third round of the storm-interrupted PGA Memorial tournament.
Poston made five birdies and two bogeys to complete a three-under par 69 third round to stand on 12-under 204 after 54 holes with Gerard on 208 after a 72 at the Jack Nicklaus-hosted event at Muirfield Village in Dublin, Ohio.
The final round was set to begin in threesomes off the first and 10th tees in a bid to finish before sunset.
Poston, who turned 33 on Monday, is seeking his fourth PGA title, his first since the 2024 Shriners Children's Open in Las Vegas.
Gerard won his only PGA title at last July's Barracuda Championship.
Poston and Gerard shared the lead at nine-under par facing long par putts on the sixth green when thunderstorms halted play on Saturday with most of the field still on the course.
When play resumed, Poston saved par from just inside six feet, birdied the par-five seventh hole from 10 feet and the par-three eighth hole from seven feet before a bogey at the ninth.
Poston reeled off three birdies in a row starting at 13, the longest putt a 13-footer at the par-five 15th, but then found a bunker at the par-three 16th on his way to a bogey.
Gerard missed his 14-foot par putt at the sixth and made bogey but answered with nine-foot birdie putts at the seventh and 10th.
He stumbled at 16 with a bogey after needing three shots to find the green then found deep right rough off the 17th tee on the way to another bogey.
American Sam Burns was third on 209 with compatriot Wyndham Clark and England's Tommy Fleetwood sharing fourth on 210.
Reigning US Open champion JJ Spaun, preparing to defend his title at Shinnecock in two weeks, finished a 68 to stand on 212.
Top-ranked Scottie Scheffler, trying to become the first player to three-peat at a PGA event since Steve Stricker won the John Deere Classic from 2009-2011, was on 213 after completing a 68.
Second-ranked Rory McIlroy, the reigning Masters champion, ended on 216 after closing a round of 71.